Emerging from 1988’s Remembrance of the Daleks, the Intrusion Counter-Measures Group have been battling malign powers and misused technology for the sake of Queen and country since 2012.

In this latest release, Group Captain Ian ‘Chunky’ Gilmore (Simon Williams), Professor Rachel Jensen (Pamela Salem) and Doctor Alison Williams (Karen Gledhill), along with their civil servant boss Sir Toby Kinsella (Hugh Ross) face a struggle for survival against mind control and insidious conspirators.

Reeling from the events of the previous season, we begin with Cavan Scott and Mark Wright’s ‘New Horizons’, where Alison is investigating a revolutionary monorail system rail which promises to transform London’s travel infrastructure.

Of course, all is not right at the ICMG itself, with both scientists under the influence and accepting imposters, including the devious Templeton, in the place of Sir Toby and Gilmore.

‘The Keep’, from director Ken Bentley, follows the real Gilmore and Sir Toby as they attempt to break out of prison; the major obstacle being that it is an impregnable fortress of Sir Toby’s own design. Meanwhile, on the outside, Alison and Rachel go on the run.

After a pivotal revelation, John Dorney’s ‘Rise and Shine’ and Matt Fitton’s ‘Clean Sweep’ take us to the heart of the conspiracy and show the team at its best; foiling an attempt to destroy the world whilst also fighting for their own survival.

Now on their fourth outing, and with events coming to a head, there are numerous references back to previous stories. These work well, setting events in context, but are subtle enough not to distract; although one particular revelation might send you listeners scurrying back to a previous Doctor Who release.

As ever, the core cast are on tremendous form and truly inhabit these characters. We particularly liked Gilmore’s boyish enthusiasm for working undercover and still hold out hope for Alison to find a boyfriend who survives past the end of an episode.

Among the guests, returning foe Templeton (Phillip Pope) is granted the space to dominate and it is great to see him unravel under the pressure. Also, Oscar Pearce also impresses as the fake-Gilmore, whose demeanour cracks to reveal something rather nasty underneath.

With more of a continuous narrative than before, this season of Counter-Measures is immersive as our heroes fight through a nest of conspiracy. Undercover, but not unsupported, there is plenty of action to enjoy in amongst the skulduggery and the tale builds to a truly climatic finale.

Extras: A fifth disc provides interviews with the writers and producer, talking about how the series was put together. We also hear from the cast including Simon Williams’ outrage at not being in the first episode!

Released in July 2015 by Big Finish Productions Ltd.

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